Please help!

Hello, i've brought a whole new pc, and then i started it up it was going great everything was fine, untill this really annoying and laud noise turned up. i tryed to open up my computer to see if anything was stocked it there but i could't see anything. so now when i turn on my computer i can go for 10 min without anything almost silent, then the noise come and i can't make it disappear, unless i turn off my computer for 30 min and start again then i can go for 10 mins again. If i just turn off and on right away it will say the noise right away. Please help, it's so annoying and it said in the description that it would't be laud.

Computer:
2 gigs
9800 Gt Nvidia geforce
Amd x2 duel core processer 5600+
windows xp sp3

I dind't know if that was nessesary but i did it anyway

Thanks in advance

 

before you do anything that will alter your computer is it under manufactures warranty. If so go that route first because once you start tinkering your warranty may be voided.

 

i know if i start to open my computer i don't have my warrenty anymore, but my computer store had all ready opened it to set up the cd-rom so i can open it when ever i want becuase my computer store broke the patch. So i have nothing to worry

 

How old is it? If it is only 30-90 days you may just be able to get another one by walking into the store and telling them you want it replaced. Any loud noise is a hardware problem there shouldn't be any problem. If it is older than the replacement period of your store then it may be worth looking around to avoid warranty servicing delays.